Hi Petronius,
Welcome to the National Gardening Association and these forums. Three different colors is rare in petunias, probably because plant breeders haven't tried for that explicitly. Petunia Tritunia Pink Vein has a white throat, so I guess that qualifies as a third "color".
https://www.hazzardsgreenhouse...
There are maybe one or two other petunia varieties that could qualify as "tricolor", but that is relatively rare in petunias. If you count Calibrachoas as petunias (they are closely related, and there are even Calibrachoa-Petunia hybrids in the marketplace), a few of those could be counted as tricolors, especially if you count the deep throat color as a separate color.
The zinnias I work with have some three-color combinations, if you consider that the color on the tip of the petal differs from the color at the base of the petal, and there is an overlap zone in the middle of the petal that creates a third color.
Commercial zinnia breeders, and amateur zinnia breeders like myself, have not gone specifically after three-color combinations. If three-colors were considered an especially desirable trait, then we would probably have a lot of three-color petunias and zinnias.
Again, welcome to the National Gardening Association.
ZM (not associated with any product or vendor mentioned or linked)
